


Secret Santa: Lights

by aellisif



Series: Secret Santa Series [4]
Category: Transformers: Prime
Genre: Awkward Sexual Situations, Cultural Differences, Established Relationship, Megatron is a good husband, Misunderstandings, Optimus is very embarrassed, Other
Language: English
Status: Completed
Published: 2020-09-16
Updated: 2020-09-16
Packaged: 2021-03-07 17:20:50
Rating: Teen And Up Audiences
Warnings: No Archive Warnings Apply
Chapters: 2
Words: 5,411
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/26501287
Author URL: https://archiveofourown.org/users/aellisif/pseuds/aellisif
Summary: Humans love multi-coloured strings of lights.Optimus is decidedly not a fan. Especially not when the strings of lights go in his cab.Megatron, as usual, can still think of something to render the whole concept interesting.
Relationships: Megatron/Optimus Prime
Series: Secret Santa Series [4]
Series URL: https://archiveofourown.org/series/1833973
Comments: 18
Kudos: 90





	1. Lights, licence plates, snow globe – check!

**Author's Note:**

> Heads-up: If you are very sensitive regarding the topic, some parts of this fic could be interpreted as sexual harassment. If so, please don’t read it. It is really more of a misunderstanding and no touching happens, but all the same.

“Way to go, Megatron.”

He opened his intake to make a cutting reply and closed it without uttering a word.

For a being that was only as tall as his servo, Jackson Darby was astonishingly adept at glowering so hard it even had an effect on Megatron.

Although the effect was greatly helped along by _knowing_ how badly he had just fragged up. One simply did not laugh at one’s own conjunx endura after not having seen them for several deca-cycles.

Even Megatron knew better than that.

He opened his intake again. “I did not mean to laugh at him,” he said and was slightly disgusted with how helpless it came out.

Jack continued glowering and also started thrumming his fingers on one of his crossed arm.

“Well?” he demanded and Megatron stared at him. Jack huffed loudly. “Apologise?“ he suggested, voice dripping with sarcasm, and Megatron flinched and looked in the direction Optimus had disappeared in.

He wanted to. Very much. He also wanted to embrace his conjunx, hold him, perhaps interface if Jack could be convinced to leave them alone. (Megatron did not need a repeat of the “Wedding Night”-incident, as June Darby liked to refer to it on top of it all. Although he was fairly certain Jack would refrain from sneaking up on them to then videotape them while they were interfacing.)

After all, Megatron had spent several solar cycles arguing and fighting his way through human bureaucracy to be allowed one single, measly visit to Earth where Optimus was currently helping Jack conduct an investigation. Megatron wasn’t entirely certain of the details of the mission, all he knew was that Optimus’ Earth truck altmode had led to this. Apparently, it uniquely qualified him to serve as both Jack’s bodyguard during the mission and an additional, highly capable pair of optics and audials.

The bodyguard part was why June had asked Optimus to help. The extra pair of optics and audials was why Fowler had agreed to endorse Optimus’ involvement with the mission with Jack’s employer – some government agency called FB-Eye or something?

Megatron did not care what they were called, he did care that this mission was taking Optimus away from Cybertron for deca-cycles on end.

Hence his endeavours to be permitted to visit. Their berth was cold and lonely and Megatron wanted his conjunx back, or at least wanted to see him as often as he could. Unfortunately, his own status as machina non grata on Earth made that difficult.

And now that he had, against all odds, succeeded, he had made sure no interfacing would be happening tonight, and he would be lucky if Optimus would even hear him out.

Megatron slumped to the ground, groaning.

Jack, still standing on the ledge where Optimus had managed to put him during his hurried transformation, glowered harder.

“Don’t expect me to feel sorry for you. You laughed at Optimus.”

Yes, he had. Because Optimus had not only forgotten that he was still carrying a passenger when Megatron had surprised him by shooting out of a spacebridge over his cab.

He had also forgotten that his undercover mission with Jack had required a disguise.

A disguise consisting of several small strings of glowing lights that were strung across the inside of his cab, an Earth licence plate that for some reason sported Megatron’s designation (seriously, what was up with that?) and an item that was too small for Megatron to see and had also smashed into small pieces when Optimus’ transformation sequence brought the items on the inside of his cab to the outside.

The sudden rain of items to the ground (including a duffel bag and Jack, who had been caught by Optimus before he could be hurt) was not the part that had Megatron erupting in helpless laughter. No. If only it was that.

No, what had him staring at Optimus in first disbelief and then doubling over was that the colourful strings of lights had clung to him during the transformation, and the imposing warframe that was Optimus Prime met his conjunx with a string of tiny red lights dangling from his left finial, while two other strings merrily blinking red and blue were decorating his chassis, wrapped around and behind his windscreens like some sort of -

Well, frankly, Megatron had no comparison. He had never even _seen_ anything the like.

So he had stopped.

And looked.

And then started to laugh, because he couldn’t help himself and Optimus looked _ridiculous._

And Optimus, who had been smiling radiantly, had stopped in confusion and then looked down at his chest and seen the strings and …

…

Well. A line of broken branches demarcated the escape route into the forest Optimus had chosen.

Megatron was left behind along with Jack, Optimus’ trailer and a crushing, acute sense of guilt.

Megatron groaned again, shuttering his optics. He wanted to disappear. No, he wanted to turn back time by fifteen kliks and send Optimus a comm instead of suddenly appearing to surprise his conjunx. Surprises were overrated anyway. Why had he listened to Jazz when that stupid saboteur suggested he surprise Optimus? He should have known better than to take advice from that walking, talking catastrophe.

“Hey.”

Megatron did not react.

A stone pinged off his armour and he raised his helm to glare at Jack, who glared right back. “Mind setting me down? I’d like to pick up my stuff before you step on it.”

Megatron ex-vented deeply and offered a servo, then carefully placed the human on the ground, where he started picking up things.

“So much for that snow globe,” Megatron heard him mutter as he engaged his comm.

Optimus rejected the call before the first free line signal had time to echo away.

Four times.

Megatron was close to whimpering. This was not how he had expected their evening to go. He had brought high-grade and Optimus’ much-cherished tarp and then a few other items that Optimus, for obvious reasons, had refrained from taking on an undercover mission.

“Jesus Christ, is this the first time you’ve landed yourself in the dog house?”

Jack had stopped picking up his things, or perhaps had collected all of them, and was now staring up at him with an incredulous expression on his face. “Or are you just too stubborn to apologise?”

“I am not!” Megatron snapped, immediately insulted. He hated apologising, like any bot with a shred of self-respect. But he would do it if the situation required it, of course. To Optimus, at least.

It was just that this was the first time Optimus had run away from him when Megatron had done something he disapproved of, and he just _knew_ that he was missing some crucial information here.

Like for example, what these strings of lights even were, and why they counted as a disguise. Megatron had expected any number of things to be done to Optimus to render him as inconspicuous as possible – a new altmode, different colours – he had not expected strings of lights.

Why was Optimus so embarrassed about them? Megatron had felt the flare from his field even from a distance, and he was utterly confused by it. Sure, they looked ridiculous, but that hardly warranted fleeing from Megatron, did it?

Jack ex-vented, put a servo to his helm – wait, no, he _sighed,_ put a _hand_ to his _head,_ see, Megatron had paid attention when Optimus practised human terminology in preparation – and groaned. “Then why aren’t you apologising already?”

“Optimus keeps hanging up on me.” Megatron sounded rather small, even to his own audials. “I don’t want him to block my frequency completely.”

Jack stared up at him again. “How about going after him, then? Not like you can’t tell where he went.”

Optimus’ path was indeed clearly visible even in the waning evening light. But Megatron knew better. “He has never run away from me so far,” he said, trying to find the words to explain to Jack why this was important, why it mattered that he give Optimus space now.

Without success, apparently, because Jack kept staring at him. Megatron ex-vented, sat down on the ground and stared at the broken branches forlornly. “Optimus has never been ashamed to be seen by me,” he said mournfully. “Not even when his plating was all dented and scratched and his paint was coming off of him and his internals -”

“Oookay, stop right there!” Jack trudged closer, looked at the things on his arms, sighed and set them on the floor before he climbed up onto Megatron’s thigh. Brave he was, Megatron had to give him that. And he wandered even closer to Megatron until the distance between their faces had reached the minimum without Megatron holding him up to his face.

“You think Optimus is ashamed of you seeing him?”

“Why else would he be hiding from me?”

Jack did that thing with his shoulders – shrubbing? No, shrugging. “You tell me. Is he hiding?”

Megatron forgot his woes for a moment and rolled his optics at the clueless human. “Yes, he is!”

Jack appeared to contemplate this for a few moments. “Okay, let’s assume that he is. What are you gonna do about it?”

“I am already trying to apologise!” Megatron said, his voice rising in volume. Jack flinched.

“Keep it down, okay? This is pretty out of the way, but there might still be other humans around, and I really don’t want to explain what I’m doing here with a giant alien robot instead of my truck!”

“Optimus is not your truck,” Megatron said indignantly. “He is _my_ truck.”

Jack slapped a hand over his optics – eyes. “Yes, well, if _you_ want to explain to the other truckers why the truck I am driving is actually an alien robot and pretty much drives himself, be my guest. And then you can explain to my boss why my mission is over and done with.”

Megatron ex-vented. For all that he was tempted, Optimus would be even more angry at him if he prematurely ended Jack’s mission.

For a few moments, neither of them said anything. Megatron pinged Optimus again and was as rudely rebuffed as the previous times.

“What are those lights, even?” he said out loud, half speaking to himself. Jack reacted, though.

“Those? Nothing special. Just something a lot of truckers do, so my boss figured Optimus should have some too. He wasn’t particularly impressed with it, but after he saw that other trucks had them, he agreed to me hanging them.”

That could hardly be the reason Optimus had run away from him. Some weird human decoration was not worth getting embarrassed about. Even if you forgot to take it out before you transformed.

Megatron pinged him again.

No answer.

“Are you sure that’s all it means?” he said and Jack sighed.

“Fine, I’ll go and ask Uncle Google if it makes you feel better! Just so you know, though, I think it’s your fault that he ran! You laughed at him.”

Megatron found the licence plate with his designation on it and frowned down at it while Jack pulled out something he recognised as an older (and very small) model of a Cybertronian datapad. “Why is he carrying around a licence plate with my designation on it?”

Jack looked up and held out a hand. Megatron gave it to him. “Again, it’s something some truckers do, my boss thought I should have one, and I wasn’t gonna make Optimus drive around with a licence plate in the window with a random female name on it. So I got this one custom-made for him. Makes for a good conversation starter, actually. Lots of the other truckers want to know who ‘Megatron’ is.”

Megatron was confused. Jack shrugged half. “The names are often the names of their wives or partners.”

“They showcase their conjunxes’ names in their windscreens?” Truly, humans were a strange species. The thread would never have crossed Megatron’s processor.

Jack shrugged again and went back to his datapad.

Megatron stared at the broken branches and started composing a message to Optimus. More a poem, actually. A poetic message. He really wished Optimus would pick up his comm so he could apologise for laughing at him.

“Uhm,” Jack said from his thigh, and when Megatron looked down, the colour of his face had darkened. “Uhm, I may have an explanation for why Optimus was embarrassed? But I swear I didn’t know about this!”

Megatron sat up straighter, immediately worried. “What is it?” he demanded and Jack groaned quietly.

“Okay, so apparently until some years ago, those lights _did_ actually mean something. A kind of code truckers used. And, uhm, the red lights, well -”

Megatron stared at him expectantly. Jack took a deep breath. “Red lights used to mean that the trucker wanted a prostitute to visit.”

Megatron stared. Jack waved his hand around. “A prostitute? Someone who sells their body to others?”

“Humans sell their frames?” Case in point: Weird species.

Jack groaned again. “NO, we don’t! Most of us don’t. Some do. Well, not their bodies, really, just – okay, they sell sex! That clear enough for you?”

They sold sex – sex – wait, humans interfaced for _money?_

“Your species is crazy!” Megatron said emphatically. Who had ever heard of something like that? Even back on the old Cybertron, Megatron had never known anyone to take shanix for interfacing. Small favours, yes, occasionally, but money? Surely no-one could need an overload so desperately that they wouldn’t have the time to find a willing bot if they didn’t want to self-service. Interface equipment was generally capable of storing quite a lot of overcharge, it wasn’t like it would reach critical levels that fast. He himself had gone stellar cycles without interfacing or self-servicing, and that had been during the war, most assuredly a stressful time.

Sure, he had been hoping to be able to convince Optimus to interface tonight when he came here, but he was hardly desperate for an overload. He simply missed his conjunx, and an overload or two would go a long way to reassure him that Optimus still trusted and believed in him.

“I’m not sure you should be talking,” Jack said, unaware of Megatron’s threads. “Anyhow, uhm, if Optimus knew what the red lights meant -”

Reality slammed back into Megatron and he groaned. Yes, that would certainly explain the embarrassment. If Optimus knew what the red lights meant, then he had greeted Megatron while decorated with human signals for interfacing.

Signals broadcasting a desire to interface _with_ humans.

Very, very definitely a good reason to be embarrassed. Megatron was well-acquainted with Optimus’ berth preferences, and he was quite certain that his conjunx, for all his fascination with them, did definitely not have any interest in interfacing aliens.

No wonder he had fled to get rid of the lights in private.

“For what it’s worth, I wouldn’t have hung the red lights if I’d known about it? I was just told that the red light is better for one’s eyes in the darkness,” Jack offered from his place on Megatron’s thigh.

He groaned again. “That is not helping me right now, human.”

“Jack,” said Jack, who knew perfectly well that Megatron knew his designation and was just not in the mood to be using it. “In any case, I think you should go after him. And apologise, and uhm, perhaps offer some help getting rid of those lights?”

Megatron ex-vented and then stood, Jack slipping off of his thigh and cursing quietly. Without another word, Megatron set out to find his conjunx and – well. See how much of the evening he would be able to salvage.

* * *

Optimus had disliked the lights from the very start, and not been happy about the licence plate in his windscreen either. (Although he had appreciated Jack’s thoughtfulness in getting him one that read Megatron’s designation.) But this was an undercover mission and Jack’s boss, unfortunately, was right in that many other truckers decorated their cabs with lights, so Optimus had reluctantly agreed.

Something he was regretting deeply right now. If he had but known beforehand, he would have continued to refuse, and knowing Jack, he would not have insisted.

But Optimus had not, had not even spent a byte on wondering what cultural significance those lights might have. After all, Cybertronians decorated themselves and their homes as well, the best example being Knock Out. And truckers spent deca-cycles on end in their trucks, so Optimus figured they wanted to feel at home. He sympathised after the first long haul he and Jack did on their mission, Jack posing as a college student trying to earn some extra money by driving trucks across the United States. Optimus, on the other hand, was a recent purchase by a company that also homed another undercover agent from the FBI – this was an important mission, with several different agents involved in different positions, all working together to stop a drug smuggling ring from using the rigs for their purposes.

Obviously, the newcomer and the new truck were paired together, and since then, they had been on the road. That was the part Optimus didn’t mind. Nor did he mind listening in on the truckers’ conversations on the radio or in the various parking lots, where he kept his audials open while Jack was in the restaurant or elsewhere.

There were benefits to being a sentient truck on this mission. Those older truckers that wouldn’t speak to Jack while he was around had no compunctions talking about him while looking Optimus over when his driver was nowhere in sight. The information Optimus gathered in turn helped Jack worm his way into the tight-knit community.

Optimus also overheard a lot of other talk, and had become acquainted with some strange human customs that, frankly, disgusted him, but that was all part of it, and he could simply delete such conversations from his memory.

To his deep regret, one fact that he was forced to retain was the definition of “lot lizard”. The concept took Optimus aback when Jack first explained why that woman was climbing into different cabs all night long, and then his feelings quickly morphed into horror when Jack elaborated further and explained about human trafficking, sex slavery and how drug addiction and prostitution often went together.

Like any being with a functioning interface mod, Optimus understood the need for release of overcharge. The part that horrified him was how many of those “prostitutes” were forced into this line of work by circumstances or, even worse, people holding power over them. And when Jack explained the concept of “slut shaming” after Optimus asked why humans didn’t simply engage in interface when they felt like it, with whom they felt like it, he was even more horrified.

Truly, humans could be just as vicious and cruel as Cybertronians. Although the only time Optimus had encountered anything akin to slut shaming was during the war, when accusations of interfacing with someone from the other faction were occasionally thrown around. But of course, that wasn’t primarily because of the interfacing; it was because interfacing with the enemy implied that you trusted them enough to power down your weapons systems and engage your interface mod. (He and Megatron had struggled with the opposite problem for quite some time after the war, since in their case, their battle protocols kept engaging, thus rendering interface impossible. Much the same went for many of their respective soldiers, which did not help to lessen tensions.)

Megatron would no doubt have rolled his optics and scoffed how predictable Optimus was, but after that little introduction to the less savoury parts of human nature, Optimus tried to be kind to the lot lizards they encountered, was very gentle in his rebuttals of their offers and even told Jack that he may let them sit inside for a bit if they were cold.

Jack thanked him and carefully explained that he didn’t think that was a good idea, because he would be giving them the wrong impression, since he was not planning on using their services.

But. Optimus had never expected that anything _he_ did could be misinterpreted as showing an interest in interfacing with one of the lot lizards.

They generally stuck to the bigger stops where there was a better chance of encountering other truckers, but Jack wasn’t feeling well and Optimus had decided that they had better take a break so he could rest for a while. Jack had dutifully gone and found himself a room in the small motel, and Optimus had stood in the parking lot and amused himself by listening to a radio programme June had recommended to him.

He hadn’t even noticed the strings of lights in his cab were still merrily glowing when suddenly, a woman appeared out of nowhere and approached him with those swinging hips Optimus by now recognised as a sign of sexual intent amongst humans.

“You look a little lonely,” the woman had purred, and Optimus had shut down the radio immediately, realising now that playing it out loud had given the impression that his driver was inside. “Want some company?”

“Thank you, I am quite content by myself,” he had replied and she had giggled.

“Oh? Then why are your company lights on?”

Optimus, not knowing what company lights were, had remained silent.

Unfortunately, she had taken it as a sign to come closer and try to climb up and open his door. “C’mon, honey, I’m not judging, and I don’t bite. Well. Unless you pay me to.”

Optimus had locked the doors immediately. “Madam, I assure you, I have no need of your services, although I appreciate your kindness.”

“Aww, don’t be shy now! There’s not much business out here, I’m sure we could come to a mutually beneficial arrangement.”

By this point, Optimus was getting anxious and flustered. She was still holding onto the doorhandle, he couldn’t well shake her off without compromising his disguise, and he couldn’t take off either without Jack. All previous lot lizards had sauntered away once he (or Jack, depending on who they approached) stated their disinterest.

“Madam, please -”

“With a voice like that, I’m sure you’re hung like a horse. Come on, hon, let me have a look? Been some time since I last had a real man between my legs.”

Owing to his recent “education”, Optimus had actually understood what she was getting at. While he had never felt a particular need to compare his spike’s dimensions to those of terrestrial equines and did not understand either why that would be considered a good thing (as far as he understood, they were rather larger than a human’s?), the fact that this woman was mentioning his interface equipment had made him exceedingly uncomfortable. It was one thing to talk to June about interfacing and sex, it was quite another to be propositioned like this by a complete stranger, and a human to boot. Even if she could hardly have known who exactly she was propositioning …

Optimus wasn’t shy about interfacing, but he did draw the line when it came to interfacing with aliens. No, thank you, not interested. He also thought that there were some things about different species that were that species’ business, and no-one else’s. The layout, size and looks of one’s internals fell into that category.

Desperately, he had offered the only solution to his dilemma that his processor could come up with. “Madam, I am not feeling well, and I only want to rest.”

She had stopped trying to open his door and blinked at him. “Come down with a bug? Oh, honey, that’s fine – I’m sure I can help you sweat it out.”

And then she had _hiked up her skirt, opened her legs and proceeded to self-service in front of Optimus_.

He had frantically tried to turn his sensors anywhere but at the human in front of him, but it had been impossible not to at least get a glimpse of what was going on. The fact that she kept her underwear on hadn’t made it any better, either, because Optimus had still been able to pick up on what was happening on infra-red.

He had promptly disabled almost every single one of his external sensors. Nevermind that that had left him virtually blind.

Thankfully, when he had continued to just sit there, completely unresponsive, she had gotten the hint eventually, gotten up and cursed at him before stalking away.

Optimus had given himself several kliks to recover. And then he had established an internet connection and dived into the world wide web to find out why exactly he had just been told to turn off his “company lights” if he wasn’t actually interested in company.

Which was how he had found out what the red lights inside his cab meant. Or had used to mean.

Why, by Vector Sigma, did Optimus have to have the bad luck to run into the only remaining prostitute around who still remembered that custom?

* * *

And that was why he was currently sitting on a rock somewhere in the middle of nowhere, trying to disentangle the strings of lights from his frame, hot with embarrassment.

Why had he not asked Jack to remove the lights first thing in the morning when he staggered out of his room, looking marginally better than the night before?

Optimus knew the answer (he was still reeling from the encounter and much too embarrassed to talk about it, _especially_ with Jack), but that did not make this situation one iota better. Megatron was still pinging him, but Optimus would not face his conjunx with these terrible lights tangled in his frame again. No, he would get rid of them, and _then_ he would return and apologise to Megatron for running away from him and not answering his comm. Yes, Megatron didn’t know what they implied. How could he, when Optimus himself hadn’t known until last night. Yes, he had only laughed because to be fair, Optimus could imagine just how ridiculous he had looked.

But those lights were coming off _now_.

Pedesteps came closer. Optimus froze, but before he could disappear further into the woods, Megatron stepped into the clearing he had sought refuge in, optics immediately going to his windscreens.

Optimus instinctively brought up his servos to cover them. Megatron grimaced. “Let me help you with that.”

“Megatron -”

His conjunx stepped closer, flexing his claws. “I believe claws might be of use in this situation.”

They most certainly would be, because Optimus’ own blunt digits were proving inefficient in the fight with the strings. Glowing with embarrassment, he lowered his servos and let Megatron at his windscreens, turning his helm to the side as Megatron slipped sharp claws into gaps and simply cut through the strings.

With their power cut, they flickered off immediately, which was already a great improvement. Optimus started relaxing. “I am sorry I ran away -”

Megatron kissed him. “I did not mean to laugh at you.”

He managed a weak smile. “I imagine I made quite a sight.”

Megatron hesitated. “… yes. Still.”

Optimus groaned, letting his helm sink forward and rest on Megatron’s pauldron. “I guess you want an explanation?”

“Jack obtained information from someone named Uncle Bugle.”

“Google,” Optimus said, and couldn’t help chuckling fondly. “Uncle Google. It is a search engine on the world wide web. For some reason, humans refer to it as ‘Uncle’.”

“Whatever.” Megatron stepped back and looked Optimus up and down before nodding. “That should be all.”

Optimus confirmed this by looking down at himself and finding not a single tiny red light still lodged somewhere. He vented out in relief. Megatron pulled him back into an embrace and kissed his helm. “Now. What happened?”

Optimus groaned, running hot with embarrassment again. “A human prostitute and I had a misunderstanding last night.”

Jack had obviously also introduced Megatron to the concept of prostitute, because he gawked at Optimus. “A human propositioned you for interface?”

“Because of the lights,” Optimus said unhappily. “I gather the code isn’t used any longer, but she must not have known that. Or perhaps she did not have a lot of experience with truckers, I do not know. We were at a very out-of-the way stop.”

Megatron growled. “Impertinent beings! Did you not tell her you weren’t interested?”

“Of course I did!” Optimus tried to clear his vocaliser of static. “She, well, she attempted to convince me otherwise.”

A beat of silence.

“And how did she do that?” Megatron asked then, voice deceptively calm. Optimus groaned into his pauldron.

“She self-serviced in front of me.”

Megatron spat static, his field going rigid. His arms clamped around Optimus, pulling him even closer.

“She did _what?”_

Optimus chose not to repeat himself, because Megatron had heard him well and good.

“My poor Optimus,” Megatron purred after a pause. “Shall I find and punish her for her insolence?”

Optimus rolled his optics and lightly smacked some plating he could reach. “She didn’t know I wasn’t human.”

“I do hope such an act would be considered impolite even amongst humans.” Megatron sounded both affronted and doubtful. Optimus could not help but smile.

“It is.”

“Well then?”

“No, you are not going to find and offline her,” Optimus said firmly. Megatron ex-vented.

“Who said anything about offlining?”

“You are not going to frighten her out of her processor either. She was rather persistent, but she did leave me alone in the end.”

"No doubt after giving you quite a show,” Megatron commented idly, moving them so he could sit on the rock, Optimus perched on his lap. “My poor Optimus.”

He shuddered. “I do not understand why some bots consider interfacing with aliens tantalising.”

Megatron hummed, rubbing circles into his back armour. “Each to their own, Optimus. Although I don’t understand either.”

“Do you know, they only have one mode for their interface mod?” Optimus said idly, sinking against his conjunx. “And they cannot even choose which one they would like. They come fully assembled.”

Megatron chuckled in his audial, then kissed it. “Is this your way of dealing with a demonstration of human interfacing?”

Optimus groaned, core heating up again. “She also mentioned that my voice implied my spike must be big.”

Megatron snorted. “Does it now.”

“Mhm,” Optimus agreed. “Humans have some strange notions about how interface equipment size relates to other external characteristics.”

“Humans,” said Megatron dismissively, “have some strange notions, period. Not the least of which is sticking coloured lights on the interior of their vehicles.”

Optimus laughed even as he hid his face in Megatron’s neck cables. “Well, I can assure you, my cab is now a strictly no-lights-zone.”

Megatron’s engine purred. “Good. I do not care to have my conjunx propositioned by humans.”

Optimus snuggled into him. “Neither do I.”

Megatron tipped his helm up and kissed him thoroughly. “Now we are clear on that, what are your thoughts on being propositioned by your conjunx?”

Optimus burst out laughing.

He was so, so glad Megatron was here.


	2. Aftermath

For all Optimus cared, that could have been the end of his ill-fated encounter with decorative strings of lights.

Megatron, though, and Optimus should have known he would, was determined to turn his embarrassing-to-horrifying experience to something else.

A few deca-cycles after Optimus and Jack had finished their undercover mission, Optimus returned to their habsuite to find all of the lights switched off and the suite bathed in a rainbow of colours emanating from hundreds of small lights attached to their walls. They twinkled and blinked and made the whole parlour look rather like one of the human towns around Christmas time.

Optimus reset his optics at the display, somewhat confused where Megatron was going with this.

Then he realised there were also strips of red light on the floor, leading towards their berthroom.

Optimus set down his datapads and followed the lights.

He opened the door to find more multi-coloured lights decorating the walls in there and Megatron spread out on the berth, strings of red lights wound around his helm like a crown, others decorating his chestplates like some strange kind of jewellery.

But for the most part, Optimus’ attention was drawn by Megatron’s spike.

Megatron’s spike, standing proudly upright, adorned from tip to base with little, blinking, red lights.

Optimus laughed so hard he sat down on the floor.

“Alright,” he gasped, “you made your point. They do look ridiculous.”

**Author's Note:**

> Inspired by one of the comments on Secret Santa, gladiator-style, where Kat liu commented that actually, giving Optimus a few strings of lights for his cabin would make a rather convincing disguise …
> 
> The myth that the red lights in a cab signal an interest in hiring a prostitute used to be quite commonly accepted as fact when I was a teenager, and it was one of two things that immediately came to mind when I read said comment, that and how utterly, absolutely ridiculous Optimus would look if he transformed and those strings got stuck everywhere in his armour XD  
> And then I wanted some relationship fluff where Megatron is a good, supportive husband, who very much cares for Optimus and will not hesitate to make a fool out of himself if he thinks Optimus needs a laugh.
> 
> And then, somehow, this happened.


End file.
